Electric-arc lamp



(No Model.)

B. A. EDWARDS.

ELECTRIC ARC LAMP.

UNITED STATES PATENT OFFICE.

EDGAR A. EDIVARDS, OF CINCINNATI, OHIO.

ELECTRIC-ARC LAM P.

SPECIFICATION forming part of Letters Patent No. 400,198, dated March 26, 1889.

Application filed December 1, 1886. Serial No. 220,390. (No model.)

To all whom it may concern:

Be it known that I, EDGAR A. EDWARDs, a citizen of the United States, and a resident of Cincinnati, Hamilton county, Ohio, have i11- vented a new and useful Improvement in Electric-Arc Lamps, of which the following is a specification.

Mypresent invention relates to electric-arc lamps, and more especially to that class of lamps designed for use in locomotive headlights and similar uses where they are subjected to severe shocks and jars; and it consists in a focusing-lamp so constructed and arranged that the arc will always be maintained in the focus and the electrodes willbe properly supported and connected, so that they will not be liable to become deranged by the jars and shocks due to the movements of the locomotive.

In carrying out my present invention I make one of the electrodes of the lamp stationary or fixed when the lamp is burning, and arrange it so that it will always occupy a fixed relation to the focus of the reflector, and in order to maintain it in this position for a great length of time I make this electrode of non-consuming conducting material-such, for instance, as pure or red copperwhile the other electrode may be of the usual combustible material, as carbon, and is moved and fed by suitable automatic mechanism to maintain the arc.

In order to prevent any displacement of the ends of the electrodes or any liability of deranging their alignment, I apply a clamp or brace to the fixed electrode at or near the end thereof, which extends to and forms a guide for the moving electrode, the guide or clamp being suitably insulated to prevent the passage of the electric current through the same. By this arrangement one of the electrodes is fixed in the proper focus, and the other is guided and sustained near its end, so that the points cannot be jarred or strained out of alignment, and I am thereby enabled to produce a lamp that is capable of establishing and maintaining the arc in a fixed point in relation to the reflector, and that is in allrespects a practical focusing-lamp.

In the accompanying drawings, Figure 1 is a side View of a focusing-lamp embodying my present invention, and Fig. 2 is a detail view of the clamp and guide.

The base 1. of the lamp may be secured to the lantern-slide or head-1i ght platform of the head-light case, and may be provided with suitable guides or a socket, 2, in which the standard 3, which supports the lamp, is adjustable. From this standard projects an arm orbracket, a, from which one of the electrodes, 5, extends, the said electrode preferably being formed with a hooked or crooked end, 6. This electrode may be fixed to the arm or bracket, or may be connected with and operated by any suitable mechanism to establish the are. In any event it is arranged so that it maintains a stationary position and a predetermined relation with the reflector 7 when the lamp is in operation. I preferably make the whole of this negative electrode of metal, as I find that material well adapted for the purpose; but in all cases the tip at least is made of some non-consuming material, as pure or red copper; but I'do not of course limit my invention to such material alone. The positive electrode 8 is preferably made of carbon, and I have shown it supported in the carbon-carrier 9, which is connected with and operated and cont-rolled by any desired mechanism in the usual manner to regulate and maintain the arc.

In order to keep the points of the electrodes always in line and prevent any lateral motion of the moving carbon, I apply a clamp, 10, to the negative electrode, it being separated therefrom by suitable insulating material, 11, and adjusted by suitable means, as a screw, 12; and connected to the clamp is a guide, 13, having an opening through which the upper-carbon electrode 8 may smoothly pass and at all times be supported against any jarring or shaking from the locomotive. The parabolic reflector 7 may be supported in any desired manner, as in the frame of the head-light or from the platform of the engine or otherwise, and the electrodes project within the reflector, so as to cause the electric arc to be maintained at the focus-point thereof. If now a current of the proper relative strength and electroanotive force be used in the operation of the lamp, the carbon electrode is disintegrated and the particles thereof are carried to and deposited upon the copper tip of the negative electrode, forming a thin film thereon and protecting the copper from destruction by the action of the electric current, and it is thus rendered practically noi'i-consuming. It will thus be seen that as the negative electrode is always in proper relation to the focal point and is not consumed, and as the positive electrode is held in alignment therewith, I am enabled to produce a focusinglamp that is steady and constant under the varying motions of the locomotive.

It is evident that my present invention is not limited to any particular construction of the operative parts, and I have not deemed it necessary to specifically describe them, as any one skilled in the art will understand their construction and operation.

IVhat I claim is 1. In a focusing arc lamp,the combination, with a movable or adjustable electrode and mechanism to adjust the same, of a non-consuming electrode and a guide embracing the movable electrode at or near the tip thereof, substantially as and for the purpose set forth.

The combination, in a focusing-lamp,

with a movable or adjustable electrode of carbon or equivalent material, of an electrode 0 of copper and a guide embracing the movable carbon electrode at or near the point thereof, substantially as set forth.

3. In a focusing arc lamp, the combination, with a movable or adjustable electrode, of a non-consuming electrode and a clamp secured to the fixed electrode at or near the tip thereof and having a guide to receive the movable electrode at or near the tip thereof, said clamp being insulated from one of the electrodes, substantially as and for the purpose set forth.

at. The combination, in an electric lamp, with an automatically movable or adjustable carbon electrode, of an opposite electrode of copper, a tip or point of deposited carbon upon the end of said copper electrode, and a guide arranged to guide the movable carbon electrode at or near the point thereof, substantially as herein set forth.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

EDGAR A. EDWARDS.

\Vitnesses:

F. L. FREEMAN, WM. A. HARRIES. 

